Preview of Fall 2009 iMacs: Apple iMac 21.5- and 27-Inch Models

The fall 2009 edition of Apple’s iMacs will more than satisfy almost any desktop user. With color accurate displays in new 16:9 ratios, your desktop will look especially good, though you may find yourself watching HD movies when you should be working.

When you finally do decide to get to work, the new Quad-Core processor options on the 27-inch model will have you zooming through tasks. There may be enough time for an HD movie or two after all.

The fall 2009 edition of the iMac line of Macintosh computers ushers in more than just an upgrade or speed bump. It brings distinctive new style and improved performance and capabilities to the iMac family.

Each of the four models in the new iMac lineup has its own specifications, but they have much in common, well beyond the same body style, which happens to remain distinctly Apple and distinctly gorgeous. The latest styling uses a glass monitor bezel that is flush, edge-to-edge, with the iMac’s aluminum frame. This produces a seamless frame, with no visible joints, as well as the impression that the iMac’s monitor stretches out beyond its apparent size.

Both the 21.5- and 27-inch iMacs use IPS panels, which are well regarded as having the best color accuracy and widest color gamut of LCD displays. They also offer very wide viewing angles, just the thing for showing off your latest video creation to colleagues. The displays also offer true 16:9 wide screen ratios, with the 21.5-inch coming in at 1920x1080, a true HD resolution, and the 27-inch achieving 2560x1440. If you’re thinking that these iMacs would make great HD monitors, it appears that Apple agrees. The 27-inch model’s Mini DisplayPort supports bi-directional connections, so you can connect an HD source to your iMac and use its display as an HD monitor. Apple will provide adapters to allow this video connectivity later in the year.

Memory for the new iMacs has gotten an update as well. With 4 SO-DIMM slots, the new iMacs can support up to 16 GB of RAM. What’s not clear at this early writing is whether the 16 GB RAM limitation is due to the lack of memory modules larger than 4 GB or the design of the memory controller circuitry in the new iMacs. Either way, it’s a big improvement over the older design that used only 2 SO-DIMM slots. It also corresponds to one of the most asked for new features in an iMac: more RAM space.

Apple has made three different Intel processors available for the new iMacs. The two 21.5-inch models can use a 3.06 GHz or 3.33 GHz Intel Core 2 Duo processor. The fun begins with the 27-inch model, which can be configured with the same two Intel Core 2 Duo processors, or with a 2.66 Quad-Core i5 Intel processor, or a 2.8 GHZ Quad-Core i7 Intel processor. Both of the new Quad-Core options bring the kind of performance first seen in the Mac Pro to an all-in-one desktop. Both new Quad-Core processors offer a turbo mode that lets the processors idle along at slow speeds when little or no work is being performed, and then zip along to clock speeds beyond the speed rating for quick bursts of work. Burst speeds can be as high as 3.2 GHz for the i5 and 3.46 GHz for the i7 processor.

The new iMacs, especially the 27-inch models that can serve as HD monitors, may be the best iMacs yet. Add in the Quad-Core option and you have a beast of a system, hiding in plain sight on your desktop.